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I made mine from about 20' of plastic tubing from Lowe's mounted with zip ties to a cool yellow aluminum yardstick.
With center of the tubing at the bottom of the stick, the tubing runs up each side to the top of the stick and then to each throttle body.
Tubing is filled with ATF, which is red and looks good with the yellow yardstick(very important).
I hang it above the bike and there's about 7' of tubing to run to each TB.
With the ATF level at the halfway point on the stick, there's time to correct the setting or shut the engine off to prevent the atf from going over the top, if the tb's are too far off.
It's just a big U shape hung on a stick.
Total cost; about 12.00 bucks.

I'm curious, how close are the levels and how much do they fluctuate when the TB's are "balanced"

I made mine from about 20' of plastic tubing from Lowe's mounted with zip ties to a cool yellow aluminum yardstick.
With center of the tubing at the bottom of the stick, the tubing runs up each side to the top of the stick and then to each throttle body.
Tubing is filled with ATF, which is red and looks good with the yellow yardstick(very important).
I hang it above the bike and there's about 7' of tubing to run to each TB.
With the ATF level at the halfway point on the stick, there's time to correct the setting or shut the engine off to prevent the atf from going over the top, if the tb's are too far off.
It's just a big U shape hung on a stick.
Total cost; about 12.00 bucks.

heh heh

Before I got the advise to break off Q-tip ends into the tubing to baffle the oscillations I made one, only 6ft tall, with water.
The 1100 sucked all the water out in about 2 revolutions and didn't even have the decency to misfire.
My manometer got blowed out the tailpipe in a little cloud.
Hope yours goes better.

I made a two bottle manometer (as I described in post #10) a few weeks ago. It worked great. I like that there is no way for the liquid in the device- water with red food color, in my case- to get into the carbs. That came in handy at first while I was playing with the adjustments on the carbs- they were way out of balance to start out. I might have taken pictures- if so I'll load them up to this post later.

So I took a look at the site http://www.powerchutes.com/manometer.asp and the first thing he states is "The objective of the vacuum measuring carb synchronizer is to see that the vacuum signals from both carbs are the same. It is the difference between the signals and not the actual signals we are interested in" so I could be seeing -15pa on the right side and -10pa on the left and if I got both to the same number would be the goal and it wouldn't matter if I went with the -15pa or the -10pa? I'm not the brightest bulb on the shelf but I do use a Manometer as part of my job but I never thought I could use it to sync my throttlebodies and I'm just trying to grasp it.

I think you mean use one actual manometer and move it from one side to the other, back and forth.
Sure.
At a given throttle position.
You would have to hold the throttle steady while moving the hose. difficult

Can you get two such manometers? so you can see both sides at the same time?
This would be much easier to implement, but yes, at a given throttle setting, and rpm, the vacuum will be the same on both sides, since all the pertinent parts are identical side-to-side.

I think you mean use one actual manometer and move it from one side to the other, back and forth.
Sure.
At a given throttle position.
You would have to hold the throttle steady while moving the hose. difficult

Can you get two such manometers? so you can see both sides at the same time?
This would be much easier to implement, but yes, at a given throttle setting, and rpm, the vacuum will be the same on both sides, since all the pertinent parts are identical side-to-side.

Nice! This is what I use at work (energy auditing) and you can see both sides at the same time.

Mercury?

I think its still available if you shop, maybe pricey! Its the fluid of choice for measurement devices as this for a century. Very heavy liquid and makes the device reasonable in size to manage. Just don't spill it! I have not bought any mercury in a LONG time, so maybe its not practical anymore. I know a very small amount of it, as in an ounce weighs a LOT and works really well in a gauge as described. Just a much smaller gauge to handle is only real advantage. I use TM today for last 15 years. Randy

This is my first try at a 2-bottle manometer (cue the muppets). A little more technical to put together than the single tube with ATF, but I liked the way it worked out. I used water with a little food coloring. It was important to only fill each bottle about one-third or so (in case the carbs were so out of balance that all the water ended up in one bottle or the other, the bottle didn't end up overflowing). It was pretty easy to use and the bike is running sweetly with the carbs balanced.

coming to this late, but just want to add that the physics of the vacuum does not depend on tube length, but the critical thing is your tubing must not collapse, so it has to be pretty stiff esp where it connects to the brass nipples at the engine.
Aquarium tubing will collapse with heat and make your efforts less than useless.

It seems to me it's easy enough to make the two limbs close to equal so why not. But, it has to stay open during the procedure.

John

PS there's lots of chatter around about the fluid to use within. You're looking for the Goldilocks fluid, not too light, not too thick and visible. ATF works for me using hospital suction tubing swedged on to one foot of vacuum hose--from advance auto and sealed to prevent leaking, sucking air.